Self transforming to power law topology for overlay networks. Dr. Suyong Eum Copyright ⓒ 2009 OSAKA UNIVERSITY. All rights reserved. Prepared by Dr. Suyong Eum

Background. Proposed method. Simulation results. Conclusions. Presentation Outline Background. Power law topology. Self organization system. Proposed method. Simulation results. Conclusions.

Background – Power law topology? Degree of a node? e.g). (ki): degree k of node i Node degrees over a network are characterized by a distribution function P(k). Robustness & small diameter. P(2) = 4 / 9 P(3) = 4 / 9 P(4) = 1 / 9 1 2 3 P(k) 4 5 6 7 8 9 k

Background - Self organizing system No central control. Emerging global property. No single failure. High Scalability. High Security. Self organizing systems No central control : There is no global control system or global information available. Each subsystem must perform completely autonomously. Emerging structures: The global behavior or functioning of the system emerges in the form of observable patterns or structures. Resulting complexity: Even I the individual subsystems can be simple and perform basic rules, the resulting overall system becomes complex and often unpredictable. High scalability: There is no performance degradation if more subsystems are added to the system. The system should perform as requested, regardless of the number of subsystems.

Background – Needs of future networks Power law topology Low diameter Robustness Self organizing Mechanism Scalability Security Low diameter Robustness Scalability Security Self organizing Power law topology

Proposed method. Step (1) Step (2) i j ki kj (A) (B)

Simulation results - (1). β=0.0 β=0.1 N=1000, E=8000, N^2 times rewiring. β=1.0 7

Simulation results – Robustness (2).

Simulation results – Efficiency (3).

Conclusions A power law topology emerges through the proposed rewiring scheme with the energy function. The proposed evolution model runs in a self-organizing manner, which provides scalability and security for the system. The performances of evolved topologies were evaluated in terms of robustness and efficiency. The former and the latter enhance robustness and efficiency of evolved topologies.

Questions and Problems Thanks for your attention Presenter : Dr. Suyong Eum E-mail : suyong@ist.osaka-u.ac.jp